VLANs are supported with XenServer. To use VLANs with virtual machines use switch ports configured as 802.1Q VLAN trunk ports in combination with the XenServer VLAN feature to connect guest virtual network interfaces (VIFs) to specific VLANs (you can create new virtual networks with XenCenter and specify the VLLAN IDs).
 
 XenServer 6.1 removed a previous limitation which caused VM deployment delays when large numbers of VLANs were in use. This improvement enables administrators using XenServer 6.x and later to deploy hundreds of VLANs in a XenServer pool quickly.